Do output voltage of amplifier for single power does not fall below 1 V?

Question:

The output voltage of an operational amplifier for a single power supply does not fall below 1 V.

Answer:

The output voltage will not fall below 1 V if a single power supply is used. If an output voltage in the neighborhood of 0 V is required, the characteristics at a low voltage can be improved by inserting a resistor (2 to 5 kΩ) between the output pin and GND for pull-down. This characteristic is caused by the saturation voltage of the output transistor. To handle a signal in the vicinity of 0 V, two power supplies, of positive and negative polarities, are necessary. The minimum output voltage ranges between approximately 0.6 and 1.5 V from the voltage of negative power supply (ground potential in the case of a single power supply). Note that the output impedance substantially increases at a voltage lower than this.